walk in
by Doodleniks
Summary: Mob leaves something at the office and goes back to get it. He walks in on his boss and coworker kissing. Reigen/Serizawa.


Mob had gotten halfway through his walk home when he realized that he had left his schoolbag at the office.

The realization came with a soft 'oh' when he went to check if his phone was in his bag, only to see that there was no bag at all. A more thorough check revealed his phone was nowhere on his person, so the probable answer to his initial question was yes, it was in his bag, except his bag was back in the office.

Mob stared at the road in front of him, wondering the time, and if it would be better to just wait till tomorrow to pick it up. The cold air brushed his hair, making his too long bangs whip his face. It would grow colder again if he walked back.

But his homework was in his school bag. A rare math assignment completed with Serizawa and Reigen's help (Serizawa actually working through the problems and showing him how they were done, Reigen just punching them into an online calculator and giving the answers to Mob as if he had solved them himself). He really couldn't miss another assignment. And it would sting more if it was one he had actually completed.

He turned back. The longer he waited, the longer it would take.

About a year ago, with a series of grand flourishes, Reigen had presented Mob with a key to the office. "You've been working here long enough to be trusted with this," he'd said. "Just in case you need to come into the office for whatever reason. Don't lose it, though, or the money to rekey the office comes out of your paycheck." He had tapped Mob on the head with the key, then rustled his hair and dropped it in his palm.

Mob rarely spent any of his earnings, but he still took fastidious care of the key. It never left his person, except when he was afraid it might fall out of a short pocket. Sometimes he would reach into his pocket and feel for the shape of it, and a small glow of pride would light inside of him. He had never had a reason to use it before now, and had been looking forward to it on the walk back.

However, he realized when he put his key in the lock that there was no need. The door was already unlocked. Hadn't Master locked the door when they had gone down to the ramen shop, all three of them together? It would be very unlike him to forget, but not impossible. Turning the key in the lock anyway, Mob opened the door and stepped in.

The office was quiet enough that Mob could hear the floorboards squeak underneath his feet. He knew where his bag was- he had left it on the couch where he had worked on his homework. He could just grab it and then lock the door on his way out. Mob lifted his head to scan the office and stopped short.

He had not spotted them immediately since the office lights were still off, but Serizawa and Reigen were still in the office. Reigen was sitting on his desk, with Serizawa standing unusually close to the other man. Their height difference was pronounced as it was, but without the aid of Reigen's cartoonishly long legs, Serizawa towered over him. However, he was bent at the waist, bringing their faces close together.

Mob realized that his master was not truly sitting on the desk. He instead hovered a few inches off the desk, the tips of his fingers hooked under the edge, and Serizawa's huge arms caging his waist. Mob felt the pressure of Serizawa's psychic energy at work in the room, and after he peeled his gaze away from the two, he realized that Master was not the only thing floating. Stray pieces of furniture drifted around the room- a potted plant spun in air, and Mob spotted his schoolbag, strap caught in the couch but tugging upwards towards the ceiling. Were they in some kind of trouble? Mob tilted his head, trying to get a better look at their faces.

It was then he realized that the reason Reigen and Serizawa were standing so close was because they were kissing.

Mob was not really sure what to do with that information.

He was aware that generally speaking when people kissed, they would rather do it alone. But he was already here, and that particular rule had been broken. Of course, neither of them had _noticed_ him yet- both of them seemed pretty absorbed with what they were doing. His eyes tracked from his master, to Serizawa, to his schoolbag, back to his master.

They were still kissing.

A little aghast, Mob decided he needed to leave as soon as he could. The shock was fading enough for him to realize he should be embarrassed, and being out of the room was top priority. He could just go stand outside until they were done, but the only way he would know is when they came out, and then he would have to make up an explanation, which he was terrible at. He could also just leave his bag and run home, but the completed math homework still beckoned.

The bag wiggled at him, drawing his gaze mercifully away from them. Maybe, just maybe, he could use his powers to get the bag and its contents, now strewn around the room, without them noticing. And then he could leave, and it would be like he had never been here.

Out of the corner of his eye, Serizawa moved one hand up to hold Reigen's face, the curve of his cheek resting into the other man's hand. Reigen sighed gustily, and this was now in fact worse than the time Mob had wandered into the kitchen to find his mom and dad slow dancing to music in the radio with their faces mashed together. Mob hurriedly raised his hand and after a few moments, his focused energy won over Serizawa's unconscious powers. The bag pulled free of the couch and from around the room, his belongings collected, placing themselves neatly in the bag, his phone landing in his hand and his bag on his shoulder.

Mob peered inside the bag to ascertain that everything was where it should be, and then peeked back at the two. Amazingly, they hadn't noticed. Even though he was beginning to suspect the room could collapse and they would still be doing that, Mob slowly stepped backwards, agonizingly aware of the creaks each floorboard made under his feet.

In an unprecedented move, Reigen pulled his face away from Serizawa. Fortunately, his eyes didn't move from the other man, giving Mob a better look at his master's face. It took a moment for Mob to place the expression. It was a happy one, but in a different way than Mob usually saw from him. It was too relaxed and soft for it to belong to his master's usual array of face splitting grins, and the calmness in his eyes unsettled Mob even more. The extreme stillness was at contrast of everything Mob had ever known about his master. He hurriedly reached for the knob before another weird thing could happen.

At that moment, his phone chose to ring.

Serizawa's shoulders tensed, and Reigen's unfamiliar expression blinked away back to a confused look that Mob knew well. Maybe if Mob had been faster, he could have sprinted out the door before Reigen managed to look at the at the source of the noise, but he had frozen in place as soon as his phone began to make the offending noise.

Reigen's eyes tracked to the source of the noise and landed on Mob. For a moment, his face maintained the same expression of mild confusion. Then his eyes widened and he half screamed, turning a deep red that spread from his neck to his forehead like a rising thermometer. He released the desk and flew towards the ceiling, Serizawa frantically grabbing at him as he sped by. He managed to seize Reigen's ankle. It jerked the man to a stop in mid air, but as soon as Serizawa turned to see what had caused Reigen's distress, he released him in a similar shock. Mob watched in mute horror as Reigen collided headfirst with the roof, a fine sprinkle of dust and plaster shedding onto him. The rest of his body tilted to follow until he was pasted spread-eagled against the ceiling.

"Reigen!" Serizawa squawked, hands twitching in the beginnings of a panic. "I'm sorry!"

Most of the furniture was traveling to join Reigen, creating a series of crunching noises that he flinched along with. He made a response, the details of which were muffled since his face was crushed against the ceiling.

"What?" Serizawa said, voice raising in pitch and volume. "Reigen, I can't hear you-"

Reigen managed to pry a finger away from the ceiling in a herculean effort. It pointed at Mob, then downward.

"Oh," Serizawa said, voice dropping. He shuffled awkwardly to face Mob once again. "Could you…"

Mob swallowed and raised his free hand, trying to overcome the other esper's out of control powers. Most of the furniture came down without trouble- Serizawa was getting better at reining in his abilities. But the focal point of his overrun emotions, Reigen, remained stubbornly adhered to the ceiling.

"I think you'll have to get him down, Mr. Serizawa," Mob said, dropping his hand.

The other man paled even further. "O-okay. I'll see if I can." Reigen made a small, panicked noise at the word _if_.

After a moment of deliberation, Serizawa carefully climbed onto the desk, making him almost level with the ceiling and the back of Reigen's head. He reached his long arms up and after a moment, pulled the him free from the ceiling with a loud pop.

As he pulled Reigen down, Reigen grabbed frantically at him, wrapping his arms around his neck. _"Don'tletgo,"_ he said rapidly, legs swinging around to cross behind Serizawa's back. "I'm still wanting to go back to the ceiling, so… don't let go."

It was easy enough to see that he was correct- his hair was standing on end, wafting in an invisible breeze, and his tie formed a straight line in between their faces. Serizawa flushed and nodded, repositioning his hands so he had a better hold on the man's waist. For a moment, they stood there, Reigen tangled in a knot around Serizawa, faces practically flush against each other. Mob was afraid that they were going to start kissing again, but Reigen managed to break eye contact with Serizawa. He looked briefly at Mob, then quickly trained his eyes on the floor again. "Okay," he said. "Think you can get us on the ground, Kat- Serizawa?" His face was still red, but Mob couldn't tell whether it was still embarrassment or from the ceiling pattern being indented into his skin.

Serizawa nodded, and after a few moments of wobbling, he clambered down from the desk, Reigen yelping directions as they went. He settled onto the floor, and breathed out, a bit more relaxed than before. Reigen nestled his head briefly into his shoulder, murmuring something Mob couldn't hear, and a slow, shaky smile spread across Serizawa's face.

Then the two of them collectively remembered Mob's existence. Reigen pulled his head away and coughed, creating a triangle of space between his chest and Serizawa's. Serizawa focused quickly on an empty square of wall behind Reigen's head.

"Er, Mob." Reigen released Serizawa's neck in the beginning of a gesture, then frantically wrapped them back into place when he began to lift away. "Serizawa and I, we were just…"

"Kissing," Mob said. "I know."

"No, no!" Reigen managed to force his hands still. "An evil spirit… Had seized control of my face. And Serizawa was destroying it." Serizawa was going deeper shades of red by the moment.

"Master, I'm fourteen," Mob said. "I know what kissing is." He had been hoping that as soon as they had gotten Reigen down, he could make a speedy exit and pretend this had never happened. Ignoring things that had happened and pretending they had not altered him irreparably was a special skill of Mob's. Reigen, however, seemed determined to prevent that.

"Shit, they start kids young these days," Reigen muttered. "Why'd you come back anyway?"

Mob raised his bag as an explanation. "I left my schoolbag."

"Let this to be lesson to you, then," Reigen, with the dignity of a man who wasn't at present trying to rearrange his legs into the least awkward position because if he didn't hold onto someone he would slam against the ceiling. "Keep track of your possessions, or terrible things will happen."

At this moment, Mob's phone rang again. Serizawa jumped a little, and Reigen's head clonked against his. "You better answer that, Mob," Reigen managed, wincing. "It's probably your brother. He's been calling."

A closer look at his phone revealed a litany of missed calls from Ritsu. Hurriedly, Mob answered. "Hello?" He asked.

"Mob?" Ritsu's voice crackled through the speaker. "Are you all right? You should have gotten home an hour ago. Mom was wondering where you were, and when you didn't answer we got worried."

"I'm okay," Mob said, still staring at Reigen and Serizawa. "We got done a little late today. I realized I had left my schoolbag at the office on the walk home, so I came back to get it." Serizawa was attempting to sit on the couch while still maintaining a steady grip on Reigen. He sat on Reigen's foot accidentally, and sprang up quickly at the man's squeak of pain.

"Oh," Ritsu said, relief audible. "So are you on your way home now?"

"No, I'm still at the office," Mob said. "I had to help out Master and Mr. Serizawa."

Ritsu paused. Serizawa was now examining the top of Reigen's head, picking out pieces of plaster stuck to his hair. "Help out with what?"

"They were-"

"WORKING," Reigen bellowed through cupped hands. "WE WERE _WORKING."_ Serizawa grabbed him before he could float away completely and yanked him down again. After a few moments of repositioning, Reigen sat turned sideways on Serizawa's lap, arms hooked around each other. Reigen stared at Mob expectantly.

"…Working," Mob said.

The silence on Ritsu's end gave Mob the feeling that Reigen's shouts had not gone unnoticed. "…What kind of work?"

"Oh, um," Mob searched for an answer. Reigen gave a series of meaningless pantomimes while Serizawa grew more and more visibly uncomfortable. "Massages."

Reigen's eyes bugged out, and he slapped a hand to his face, dragging it down in an exaggeratedly slow movement. "Massages?" Ritsu's voice had an incredulous hitch to it.

"Just the one," Mob said, watching as Reigen floundered around in his apparent death throes. "A customer came in late. I didn't help with it, though, just, ringing it up." His voice trailed off towards the end, excuse growing lame even to himself.

"You're a terrible liar, you know that, Mob?"

"Yes," Mob said. "I'll be home soon, sorry about this. I already ate, so no need to wait up."

Ritsu's sigh was long. "Okay, okay. You know I'm going to pry the truth out of you later?"

"Yes," Mob said, again.

"Okay. Be safe coming home. Bye, brother."

Mob nodded, remembered that his brother couldn't see him, and said, "I will. Bye, Ritsu." He ended the call.

A few moments after the call ended, Reigen groaned loudly, the arch of his back increasing with the length of the noise. As soon as it ended, he snapped back to ramrod straight posture.

"I should go home now," Mob said. "My family is expecting me."

" _Massages_ , Mob? _Really?_ We haven't done one of those in _months,"_ Reigen said, pointing an accusatory finger at him. Serizawa mumbled something about how _actually, they had done one a couple days ago_ , but Reigen flapped his hand. "Back me up on this, Serizawa! Massages. Ridiculous."

Mob edged a step backwards. "I'm really sorry I interrupted. Can I go?"

"No!" Reigen snapped, then paused. "Actually, I don't have a reason to hold you here. So, I guess. Yes."

"We were going to tell you soon," Serizawa blurted.

" _KATSUYA,"_ Reigen howled.

"Well, we were!" Serizawa's voice took on a defensive tone. "And I mean, now would be a good time, wouldn't it? He knows. We're all. Here." His head bobbed around in a circle at Reigen and Mob.

Reigen's face contorted in mock agony. "UUUuuuuuuuu _uuuuuggh_. Ugh." He flopped backwards on the couch, hands pinwheeling out, leaving Serizawa to catch him. "You're right, of course. Why did you have to pick now to grow a spine?"

Serizawa shrugged, pulling him upright again. "Sorry, Mr. Reigen."

"Don't call me that," Reigen said, whacking a hand against Serizawa's chest.

"Sorry, Arataka."

Reigen drew in a deep breath, chest puffing up as he pulled air in. Then he pointed at Mob. "Serizawa and I are dating."

"Have been for a few months now," Serizawa added.

"And we thought you deserved to know, because we care about you!" Reigen's tone was somehow combative.

The rehearsed speech petered out, and the two of them stared of Mob, a combination of expectant and uncertain- but not necessarily from who he usually associated those emotions with. "Um," Mob said. "Okay."

They blinked at him. "That's it?" Reigen said, sounding almost hurt.

"I'm very happy for you," Mob offered. "But I really do need to go home now." He repositioned the strap of his book bag on his shoulder, wishing he could do something about his discomfort. It was not that he was disgusted. It had just been a series of awkward events that Mob had no idea how to navigate- something more exhausting than any spirit Mob might have to face.

Reigen and Serizawa looked at each other. Reigen snorted. Then, to Mob's complete confusion, he began to laugh. "Well," he said, between snorting fits, "I don't really know what else I expected." Another cackle of laughter, and a tear squeezed out onto Reigen's cheek.

"Master, you're crying," Mob said, unable to suppress his alarm. It felt like someone had picked up the box that was Mob's world and dumped it out, revealing new facets on all the pieces. In the years that Mob had known his master, he had never cried.

Serizawa swabbed the tear away with a thumb. Reigen snorted again and buried his face into his shoulder. "I don't really get it, either," Serizawa said to Mob. "But thank you. He was worried about this."

"You're welcome," Mob said, completely unsure if that was the correct response. "Is Master okay?"

"Go home, Mob," Reigen mumbled from Serizawa's shoulder. "I'm fine."

Mob hovered hesitantly in front of the door, but Serizawa waved a hand at him. It occurred to him he finally had what he had wanted since he had walked in: a way out. So he nodded. "Okay. Bye, Master and Mr. Serizawa. I'll see you tomorrow." He rested his hand on the door handle, when a thought occurred to him. "Oh- you don't need to hold onto Master anymore, Mr. Serizawa. He's not going to go flying anymore." He had noticed earlier the relaxation of Serizawa's psychic powers, but there had no good time to say anything.

Serizawa bit his lip. "I don't want to take chances, but thank you, Shigeo."

"Okay," Mob said. He turned the door handle, then made his hasty exit.

The door clicked shut behind him, and Serizawa sat quietly on the couch, letting Reigen's laughter relax into shaky sobs, then into nothing. "I guess we shouldn't be kissing in the office," he said to Reigen. He absently rubbed the small of the other man's back in a slow, kneading gesture.

"Yeah, I think the kid's traumatized enough," Reigen mumbled, laying his head on his side. "Well, Katsuya, you heard him. You can let me go now." He made no motion to move off of the other man.

"I think I'll hang on a little longer," Serizawa said, letting a hint of a smile touch his face.

Mob ran the first two blocks away from the office so he could do something without thinking about it. But his lungs and the stiffness of his school uniform eventually caught up with him, and he slowed to a crawl again, breathing in deep, shaky breaths.

Normally, Mob was able to push and compartmentalize what he did not want to think about with ease. Break it down into small pieces, imagine putting it in a container and putting that container on a shelf. But this tugged at him at a different way than most things.

He generally preferred when people were easy to understand. Master was loud and fast and constantly moving. Serizawa was soft and kind and afraid to touch in case he broke something. Most of what he had seen today had not fit the pictures he had created for them.

But at the same time. Mob thought about the calm that had settled on his master's face, and the way Serizawa had offered his own opinion without fear of retribution. Those weren't bad things. Maybe it was okay if things were harder to understand, if they could stay that way. Stay happier. Change didn't have to be bad.

Mob still didn't want to see anyone kiss anyone, though.

He resettled the strap of his schoolbag, checked that his phone was in pocket, and walked home.


End file.
